On the excellent qualities of coffee, and the art of making it in the highest perfection

1

ESSAY XVIII.

OF THE EXCELLENT QUALITIES OF

COFFEE,

AND THE ART OF MAKING IT IN THE
HIGHEST PERFECTION.

ILLUSTRATED BY COPPER-PLATES.

’ i

By BENJAMIN COUNT OF RUMFORD, F.R.S.

y

VOL, IV,

M

(

\ 1 «

ESSAY XVIII.

_/vja

' ’ ' • - -• * • ' * • * • • * . xj • - ii J * » . t, •

^HE ufe of fcience is to explain the operations
which take place in the pra&ice of the arts, and
to difcover the means of improving them ; and
there is no procefs, however fimple it may appear
to be, that does not afford an ample field for curious
and interefting inveftigation.

As thofe domeftic arts, and elegant refinements,
which the progrefs of induflry, and the increafe
of wealth and knowledge introduce in fociety,
contribute to the comfort and happinefs of great
numbers of refpedable individuals ; their improve¬
ment mufl be interefting to all thofe who take
pleafure in contemplating the profperity of mankind,
and in contributing to their innocent enjoyments.

Among the numerous luxuries of the table, un¬
known to our forefathers, which have been imported
into Europe in modern times, Coffee may be confi-
dered as one of the moft valuable.

Its

N 2

15 6 Of Coffee, [essay xvnx.

Its tafte is very agreeable, and its flavour uncom¬
monly fo ; but its principal excellence depends on
its falubrity, and on its exhilarating quality.

It excites cheerfulnefs, without intoxication ; and
the pleafmg flow of fpirits which it occafions, lafts
many hours, and is never followed by fadnefs,
languor, or debility.

It diflufes over the whole frame, a glow of health,
and a fenfe of eafe and well-being, which ie ex¬
ceedingly delightful. Exiftence is felt to be a
pofitive enjoyment, and the mental powers are
awakened, and rendered uncommonly adive.

It has been facetioufly obferved, that there is
more wit in Europe fince the ufe of Coffee has be¬
come general among us ; and I do not hefitate to
confefs, that I am ferioufly of that opinion.

Some of the ableft, moft brilliant, and moft in¬
defatigable men I have been acquainted with, have
been remarkable for their fondnefs for Coffee ; and
I am fo perfuaded of its powerful effeds in clearing
up the mind, and invigorating its faculties, that on
very interefting occafions, I have feveral times taken
an additional dofe of it for that very purpofe.

That Coffee has greatly contributed to our inno¬
cent enjoyments, cannot be doubted ; and expe¬
rience has abundantly proved, that fo far from being
unwholefome, it is really very falubrious.

This delicious beverage has fo often been cele¬
brated, both in profe and verfe, that it does not
ftand in need of my praifes to recommend it ; I

fhali

essay xviii. *j and the Art of preparing it. 157

fhall therefore confine myfelf to the humble office of
fhewing how it can be prepared in the greateft per¬
fection *.

There is no culinary procefs that is liable to fo
much uncertainty in it's refults, as the making of
Coffee ; and there is certainly none in which any
fmall variation in the mode of operation, produces
more fenfible effects.

With the fame materials, and even when ufed
in the fame proportions, this liquor is one day
good, and the next bad ; and nobody perhaps can
even guefs at the caufe of this difference ; and what
renders thefe variations of greater importance, is
this remarkable circumftance, that when Coffee
is bad, when it has loft its peculiar aromatic flavour,
which renders it fo very agreeable to the organs of

• , . \ \ ' i '

' - • < ' 1 i - ' ' •

* If I have abftained from giving a botanical defcription of
the evergreen fhrub which produces Coffee ; with an account
of its culture, and the various attempts that have been made
by chemifts to analize its grain, it is becaufe this information
(which would neceffarily take up a good deal of room, without
being particularly interefting to moil readers) may be found in
other books.

The fame reafons have prevented my giving a hiftory of the
introduction of the ufe.of Coffee in Europe, and of the intro-

it .

du&ion of the plant which produces it, into the American
Iflands, and from thence into the tropical regions of the Con¬
tinent of America.

It is well known that this precious plant was firft found
growing wild in Arabia ; and that it does not profper, except
in very hot climates, and in hilly countries.

N 3

tafte

1 5$ Of Coffee, £ essay xviii.

tafte and of fmell ; it has loft its exhilarating quali¬
ties, and with them, all that was valuable in it.

Different methods have been employed in mak¬
ing Coffee; but the preparation of the grain is
nearly the fame in all of them. It is ftrft roafted in
an iron pan, or in a hollow cylinder, made of fheet-
iron, over a brifk fire ; and when, from the colour
of the grain, and the peculiar fragrance which it
acquires in this procefs, it is judged to be fufficiently
roafted, it is taken from the fire, and fuffered to
cool. When cold it is pounded in a mortar ; or
ground in a hand-mill to a coarfe powder, and pre-
ferved for ufe.

Great care muft be taken in roafting Coffee, not
to roaft it too much ; as foon as it has acquired a
deep cinnamon colour, it fhould be taken from the
fire, and cooled ; otherwife much of its aromatic
flavour will be dillipated, and its tafte will become
difagreeabiy bitter.

In fome parts of Italy, Coffee is roafted in a thin
Florence flalk, flightly clofed by means of a loofe
cork. This is held over a clear fire of burning coals,
and continually agitated. As no vifible vapour
ever makes its appearance within the flalk, the
colour of the Coffee may be diftinftly feen through
the glafs, and the proper moment feized for remov¬
ing the Coffee from the fire.

I have endeavoured to improve this Italian
method, by ufing a thin globular glafs veffel, with

a long

essay xvni.] and the Art of preparing it, 159

a long narrow cylindrical neck. This globular

veffel is fix inches in diameter, and its cylindrical

neck is one inch in diameter and eighteen inches

long. It is laid down horizontally, and fupported

in fuch manner on a wooden Hand, as to be eafily

*

turned round its axis. The globular veffel projeSs
beyond the ftand, and is placed, at a proper height,
immediately over a chaffing difli of live coals.
When this globular veflel is blown fufficiently thin ;
and when care is taken to keep it conftantly turn*
ing round, when it is over the fire, there is not the
fmalleft danger of its being injured by the heat,
however near it may be to the burning coals.

In order that Coffee may be perfectly good, and
very high flavoured, not more than half a pound
of the grain fhould be roafted at once ; for when
the quantity is greater, it becomes impoffible to regu¬
late the heat in fuch a manner as to be quite certain
of a good refult.

The end of the cylindrical neck of the globular
veflel fhould be clofed by a fit cork, having a fmall
flit in one fide of it, to permit the efcape of the
vapour out of the veffel. This cork fhould projeft
about an inch beyond the extremity of the neck of
the veffel, in order that it may be ufed as a handle
in turning the veffel round its axis, towards the end
of the procefs, when the neck of the veffel becomes
very hot. The progrefs of the operation, and the
moment moft proper to put an end to it, may be
judged, and determined with great certainty j not

n 4 only

I

l

160 Of Coffee , [essay xviii*

only by the changes which take place in the colour
of the grain ; but alfo by the peculiar fragrance
which will firft begin to be diffufed by it, when it is
nearly roafted enough.

This fragrance is certainly owing to the efcape of
a volatile, aromatic, fub fiance ; which did not ori¬
ginally exifl, as fuch , in the grain ; but which is
formed in the procefs of roafling it.

By keeping the neck of the globular veffel cold,
by means of wet cloths, I found means to condenfe
this aromatic fubftance, together with a large por¬
tion of aqueous vapour, with which it was mixed.

The liquor which refulted from this condenfa-
tion, which had an acid tafte, was very high
flavoured, and as colourlefs as the purefl water;
but it flained the fkin of a deep yellow colour ;
which could not be removed by walking with foap
and water ; and this ftain retained a ftrong fmell of
Coffee feveral days.

1 have made feveral unfuccefsful attempts to
preferve the fragrant aromatic matter which efcapes
from Coffee when it is roafling, by transferring it
to other fubflances. Perhaps others may be more
fortunate.

But I mu ft not fuffer myfelf to be indeed away
from my fubjeCt by thefe inter efting fpeculations.

If the Coffee in powder is not well defended from
the air, it foon lofes its flavour, and becomes of
little value ; * and the liquor is never in fo high per¬
fection

essay xviii. ^ and the Art of preparing it, 161

feftion, as when the Coffee is made immediately
after the grain has been roafted.

This is a fa£t well known to thofe who are accuf-
tomed to drinking Coffee, in countries where the
ufe of it is not controuled by the laws ; and if a
government is ferioufly difpofed to encourage the
general ufe of Coffee, individuals muff be permitted
to roaft it in their own houfes.

As the roafting and grinding of Coffee takes up
fome confiderable time, and cannot always be done
without inconvenience at the moment when the
Coffee is wanted $ I contrived a box for keeping
the ground Coffee, which I have found, by feveral
years* experience, to preferve the Coffee much
better than any of the veffels commonly ufed for
that purpofe. It is a cylindrical box made of ftrong
tin, four inches and a quarter in diameter, and five
inches in height, formed as accurately as poffible
within, to which a pifton is fo adapted, as to clofe
it very exactly ; and when preffed down into it, to
remain in the place where it is left, without being
in danger of being puftied upwards by the elafti-
city of the ground Coffee, which it is deftined to
confine.

This pifton is compofed of a circular plate of
very ftout tin, which is foldered to the lower part
of an elaftic hoop of tin, about two inches wide,
which is made to fit into the cylindrical box as
exactly as poflible ; and fo as not to be moved up
and down in it, without employing a confiderable

force*

162

Of Coffee , [essay xviu.

force. This hoop is rendered elaftic, by means of a
number of vertical flits made in the Tides of it.

On the upper fide of the circular plate of tin,
which clofes this hoop below, and in the centre of
it, there is fixed a ftrong ring, of about one inch in
diameter, which ferves inftead of a piflon rod, or a
handle for the piflon. The cylindrical box is clofed
above by a cover, which is fitted to it with care,
in order that the air, which is fhut up within the
box (between the piflon and the cover) might be
well confined.

Before I proceed to defcribe the apparatus I fhall
recommend for making Coffee, it will be ufeful to
enquire what the caufes are, which render the pre¬
paration of that liquor fo precarious ; and in order
to facilitate that inveftigation, we mufl fee what the
circumftances are, on which the qualities depend,
which are mo ft efteemed in Coffee.

Boiling hot water extracts from Coffee, which
has been properly roafled and ground, an aromatic
fubftance, of an exquifite flavour, together with a
confiderable quantity of aftringent matter, of a
bitter, but very agreeable tafle ; but this aromatic
fubftance, which is fuppofed to be an oil, is ex¬
tremely volatile ; and is fo feebly united to the
water, that it efcapes from it into the air with great
facility.

If a cup of the very beft Coffee, prepared in the
high eft perfection, and boiling hot, be placed on a
table, in the middle of a large room, and fuffered

io to

essay xvm.3 and the Art of preparing it . 163

to cool, it will in cooling fill the room with its fra¬
grance ; but the Coffee, after having become cold,
will be found to have loft a great deal of its
flavour.

If it be again heated, its tafte and flavour will
be ftill farther impaired \ and after it has been
heated and cooled two or three times, it will be
found to be quite vapid and difgufting. *

The fragrance diffufed through the air is a fure
indication that the Coffee has loft fome of its moft
volatile parts ; and as that liquor is found to have
loft its peculiar flavour, and also its exhilarating
quality , there can be no doubt but that both thefe
depend on the prefervation of thofe volatile particles
which efcape into the air with fuch facility.

If the liquid were perfe&ly at reft, the volatile
particles diffeminated in it, could not efcape ; or at
leaft not with the fame facility as when it is agitated.
Thofe at the furface of the liquid might fly off, but
thofe below the furface would be confined and
preferved.

Now all liquids, that are either heated or cooled,
are neceffarily difturbed and agitated ; and the in¬
ternal motions into which their particles are thrown,
do not ceafe, till the heating or cooling procefs has
ceafed.

As the particles of fluids are much too fmall to
be vifible, the motions which take place among
them cannot be feen; but means have neverthe-

lefs

164 Of Coffee , [essay xviii*

lefs been found to render thefe motions quite
evident.

If a fmall quantity of any foiid fubftance, in the
form of a coarfe powder, and having the fame
fpecific gravity as any tranfparent liquid, be mixed
with it, and the liquid be either heated or cooled,
the currents formed in the liquid in confequence of
the change of its temperature, will carry along
with them the vifible particles of the powder, diffe-
minated in the liquid, and the directions and velo¬
cities of thofe currents will become apparent.

The caufe of thefe motions among the particles
of liquids, that are heated or cooled, is perfectly
known.

*"• • • »• r ' •

When a hot liquid is cooled, thofe of its particles
which are the firft: expofed to the cooling influence,
on lofing a part of their heat, become fpecifically
heavier than they were before ; confequently they
become fpecifically heavier than the furrounding
hotter particles, which caufes them to defcend to¬
wards the bottom of the containing velfel.

This defcent of the particles which are cooled
necefiarily puts the whole mafs of the liquid in
motion. The warmer and lighter particles are con¬
tinually rifing towards the furface of the liquid ;
while the colder and heavier particles are defend¬
ing ; and thefe motions never can ceafe, till the whole
of the liquid has acquired the precife temperature of
the furrounding atmofphere.

When

essay xviii.3 and the Art of preparing it, 1 65

When the liquid is heated, fimilar motions take
place ; but in an oppofite direction. The particles
firft heated, being rendered fpecifically lighter by
this augmentation of temperature, rife upwards ; and
give place to the colder and heavier particles which
defcend.

Thefe motions may be rendered vifible by a very
fimple contrivance.

If one ounce of common fait be dilfolved in eight
ounces of water, a brine will be formed, which
will have the fame fpecific gravity as yellow amber ;
confequently, if a fmall quantity of that folid fub-
fiance be pounded in a mortar, fo as to be reduced
to a coarfe powder (of about the fize of muflard
feeds), this powder, on being put into the brine,
will remain fufpended in that liquid, and in all parts
of it, without either finking or rifing to its furface ;
and the particles of the amber being vifible in the
brine, will, by their motions, indicate the motions
and directions of the currents in the liquid, which
take place when the temperature of the liquid is
changed #.

If now, two like glafs tumblers be filled, the one
with the pure brine moderately heated, the other
with an equal quantity of the fame brine, at the
fame temperature, containing a fmall quantity of
the powdered amber, intimately mixed with it, on

* In order that the brine may be rendered perfectly trans¬
parent, it Ihould be filtered, or made to pals through filtering

paper.

expo*

*66 Of Coffee, f essay xviil

expofing thefe two glafs veffels with their contents,
to cool in the air, in a quiet room, no motion will
be perceived among the particles of the pure brine
(which are invifible), but the motions which will
be feen to take place among the particles of amber
in the other tumbler, will afford a convincing proof
that the apparent reft in the pure brine muft necef-
farily be a deception ; and that the particles of both
thefe malfes of cooling liquid are moft undoubtedly
in motion.

As foon as thefe liquids have acquired the tempe¬
rature of the furrounding atmofphere, their internal
motions will ceafe ; but on every change of tempe¬
rature they will recommence.

We may conceive the particles of amber, diffe-
xninated in the brine, to reprefent the particles of
the aromatic fubftance, diffeminated in new-made
Coffee : as long as the Coffee remains at reft, that is
to fay, as long as its temperature remains un¬
changed, thefe aromatic particles cannot efcape ;
for they cannot come to the furface of the liquid ;
but when the liquid is put in motion, their efcape
is greatly facilitated.

When the caufe of any evil is perfeftly known,
it is feldom very difficult to find means to pre¬
vent it.

In order that Coffee may retain all thofe aromatic
particles which give to that beverage its excellent
qualities, nothing more is neceffary, than to prevent
all internal motions among the particles of that

liquid ;

essay xviii.] and the Art of preparing it . 167

liquid ; by preventing its being expofed to any
change of temperature, either during the time em¬
ployed in preparing it; or afterwards, till it is
ferved up.

This may be done, by pouring boiling water on
the Coffee in powder ; and furrounding the machine
in which the Coffee is made, by boiling water ; or
by the fteam of boiling water : for the temperature
of boiling water is invariable , (while the preffure
of the atmofphere remains the fame,) and the tem¬
perature of fteam is the fame as that of the boiling
water from which it efcapes.

But the temperature of boiling water is prefer¬
able to all others for making Coffee, not only on
account of its eonjlancy , but alfo, on account of its
being moft favourable to the extraction of all that
is valuable in the roafted grain.

As it is well known that the heat of boiling
water is not that which is the moft favourable for
extracting from malt thofe faccarine parts which it
furnifhes in the procefs of making beer ; I thought
it poflible, though not at all probable, that fome
lower temperature than that of boiling water,
might alfo be moft advantageous in preparing
Coffee ; but after having made a great number of
experiments, in order to afcertain that important
point, I found that Coffee, infufed with boiling
water, was always higher flavoured, and better
tailed, than when the water ufed in that procefs
was at a lower temperature.

I have

1 68 Of Coffee , [essay xvixn

I have frequently taken Coffee, of the beft qua¬
lity, newly burnt, and with equal portions of it, in
powder, and equal quantities of water, have made
Coffee, in two like coffee-pots, with this fingle dif¬
ference, that the water poured into one of them
has been boiling hot ; while that poured into the
other, has been at fome lower temperature ; and I
have conflantly found, that the Coffee made with
the boiling water has been preferred by all good
judges ; efpecially when they have been prefented
with the two kinds of Coffee at the fame time,
without being told in what manner they were pre¬
pared,

I have likewife made Coffee with cold water, and
afterwards heated it ; but this I have always found
to be of a very inferior quality : it is very bitter,
and not unfrequently of a four difagreeable tafte,
efpecially when the cold water is a long time in
palling through to Coffee in powder, and when
they are fuffered to remain together over night.

The fine aromatic fub fiance is either not extraded
by cold water, or it efcapes afterwards, while the
Coffee is heating. — The fad is, that very little of
it can be perceive^ in the Coffee, after it has been
heated ; nor does Coffee, fo prepared, poffefs thofe
exhilarating qualities which render that beverage fo
delightful in its effeds, when it is made in perfec¬
tion, and taken before it has had time to be fpoiled
by cooling. As Coffee is an expenfive article,
which mull be imported into Europe from hotter

climates^

essay xvill. 3 and the Art of preparing it . 169

climates, the economy of it deferves attention ;
now it is quite certain that boiling water extracts
from the prepared grain, more of thofe particles
which give the agreeable tafte and flavour to the
Coffee, or, in other words, that give it Jlrength ,
than an equal quantity of water lefs hot : this fadt
has been afcertained by many experiments, and is
now generally acknowledged : it is indeed not a
little furprifmg, that it fhould ever have been called
in quefiiion ; for the agency of heat, in facilitating
folutions of this kind, has long been known.

As all kinds of agitation muff be very detrimen¬
tal to Coffee, not only when made, but alfo while
it is making, it is evident that the method formerly
pradtifed, that of putting the ground Coffee into a
coffee-pot, with water, and boiling them together,
muff be very defedtive, and muff occafion a very
great lofs.

But that is not all ; for the Coffee which is pre¬
pared in that manner can never be good, whatever
may be the quantity of ground Coffee that is em¬
ployed.

The liquor may, no doubt, be very bitter, and
it commonly is fo; and it may poffjbly contain
fomething that may irritate the nerves, but the ex-
quifite flavour and exhilarating qualities of good
Coffee will be wanting.

A decodfion of Jefuit’s bark is alfo very bitter,
and it is fometimes irritating, but nobody ever
found it to be exhilarating ; cuftom might perhaps
vol. iv* © render

1 70 Of Coffee 3 [essay xviii,

render the tafle of it agreeable, for even the tafle
of tobacco becomes agreeable to thofe who are in
the habit of chewing it ; but it would be difficult
to perfuade me, or any other unprejudiced perfon,
that Coffee is good, which has nothing to recom¬
mend it but a ftrong, bitter, auftere tafle.

Coffee may eafily be too bitter, but it is impof-
fible that it fhould ever be too fragant. The very
fmell of it is reviving, and has often been found to
be ufeful to Tick perfons, and efpecially to thofe
who are affli&ed with violent head-achs. In fhort,
every thing proves that the volatile, aromatic mat¬
ter, whatever it may be, that gives flavour to Coffee,
is what is molt valuable in it, and fhould be pre-
ferved with the greatefl care ; and that in eflimating
the ftrength, or richnefs of that beverage, its fra¬
grance fhould be much more attended to, than
either its bitternefs or its aflringency.

Nobody, I fancy, can be fonder of Coffee than
I am ; I have regularly taken it twice a day, for
many years, and I certainly take care to have the
very bell that can be procured, and no expence is
fprred in making it good.

The reader will no doubt be furprifed, when I
affure him, that one pound averdupois, of good
Moka Coffee, which, when properly roafled and
ground, weighs only fourteen ounces, ferves for
making fifty-fix full cups of the very bell Coffee,
in my opinion, that can be made.

The

Ess AT xvm. 2 and the Art of preparing it. 1 71

The quantity of ground Coffee which I ufe for
one full cup, is 108 grains Troy, which is rather
lefs than a quarter of an ounce. This Coffee, when
made, would fill a coffee-cup, of the common fize,

c

quite full ; but I ufe a larger cup, into which the
Coffee being poured boiling hot, on a fufficient
quantity of fugar (half an ounce^, I pour into it
about one-third of its volume of good fweet cream,
quite cold . On ffirring thefe liquids together, the
Coffee is fuddenly cooled , and in fuch a manner as
not to be expofed to the lofs of any confiderable
portion of its aromatic particles in that procefs.

In making Coffee, feveral circumffances muff be
carefully attended to : in the firft place, the Coffee
muff be ground fine, otherwife the hot water will

not have time to penetrate to the centers of the

*

particles ; it will merely foften them at their fur-
faces, and paffmg rapidly between them, will carry
away but a fmall part of thofe aromatic and aftrin-
gent fubftances on which the goodnefs of the liquor
entirely depends.

In this cafe, the grounds of the Coffee are more
valuable than the infipid waff which has been hur¬
ried through them, and afterwards ferved up under
the name of Coffee.

This fecret has been but too well known to fome
fervants abroad, where Coffee is more generally
ufed than in England, and where the preparation
of it has not been controuled by the laws. When
complaints are made that the Coffee is too weak,

o 2 they

ly-z Of Coffee, [essay xviix.

they are never at a lofs for a remedy for that evil ;
and when it has once been eftablifhed as a rule in
the family, that one ounce of ground Coffee is indif-
penfably neceffary to make a cup of good ftrong
Coffee, their point is gained.

But before we can determine with certainty how
much ground Coffee is neceffary in order to make
a cup of good Coffee, we muft afcertain the con¬
tents of a coffee-cup ; and as the fizes of coffee-
cups are very different in different countries, and
even vary confiderably in the fame country, we
muft begin by adopting fome certain fize, to ferve
as a ftandard. — The fize moft commonly to be
met with in England, and in France, is a cup which
contains 8-^- cubic inches, Englifh meafure, when
filled quite full to the brim ; when this cup is made
perfe&ly cylindrical within, and juft as high as it is
wide, it will be 2TV Englifh inches in diameter, and
confequefttly inches in height, internally.

One gill, or one quarter of a wine pint of liquor,
will fill this cup to within three-tenths of an inch of
the level of its brim, and that quantity of Coffee
will weigh 1820 grains Troy, or fomething more
than four ounces averdupois, or more exaftly 4-J.
ounces.

As a gill is a meafure well known in England,
I fhall adopt it as a ftandard meafure for a cup of
Coffee ; and as it is inconvenient to fill coffee-cups
quite full to the brim, I fhall propofe coffee-cups to
fee made of the form and dimenfions they now

8 commonly

essay xviii.] and the Art of preparing it . 173

commonly have, or of a fize proper for containing
8^- cubic inches of liquor, when filled quite full to
the brim.

As a gill is equal to 7.1875 cubic inches, about
feven-eighihs only of the capacity of the cup will,
in that cafe, be occupied by the Coffee. — Now I
have found, by the refults of a great number of
experiments, that one quarter of an ounce averdu-
pois of ground Coffee is quite fufficient to make a
gill of moil excellent Coffee, of the highefl poflihle
flavour, and quite flrong enough to be agreeable.

This decifion has been the refult of fifteen years5
experience, and as Coffee is to me by far the molt
valuable luxury of the table, with which I am ac¬
quainted, and that in which I indulge with the
greatefl pleafure and fatisfa&ion, I have fpared no
pains in my endeavours to find out how it can be
prepared in the highefl perfection : and I can fafely
affert that economy has not, in the fmallefl degree,
influenced my opinion on that fubjeCl.

I am happy when I find that improvement leads
to economy, but I have always thought that excel¬
lence fhould never be facrificed to paltry favings in
any thing, and leafl of all in thofe habitual enjoy¬
ments which are at the fame time the comforts and
confolations of life.

The fad is, with refpeCt to Coffee, that when it
is made very flrong, its tafle becomes fo .very bitter
and auflere, that it is no longer poflible to diflin-
guifh that delicate aromatic fragrance which is

03 fo

174 Of Coffee , [essay xviii.

fo liberally diffufed when the Coffee is properly
prepared.

Habit may render very bitter Coffee agreeable to
fome palates, and all perfons may not perhaps be
able to favour in perfe&ion that peculiar fragrance
which renders the fmell of Coffee fo very agreeable ;
but I am confident, that thofe who will take the
trouble to make the experiment with due care, will
find, as I have done, that Coffee, of the very belt
quality, may be prepared with the quantity of ma¬
terials above-mentioned.

But this cannot be done, unlefs the method which
I ufe be employed for making the Coffee.

In order that the advantages which will refult
from the adoption of that procefs may be perceived
and eftimated, it will be ufeful to give a fhort de-
fcription of the method formerly purfued, and to

- ■■ i-' ^ - i * * * *•

explain the difadvantages which refuked from it.

Formerly, the ground Coffee being put into a
coffee-pot, with a fufficient quantity of water, the
coffee-pot was put over the fire, and after the water
had been made to boil a certain time, the coffee-pot
was removed from the fire, and the grounds having
had time to fettle, or having been fined down with
ifing-glafs, the clear liquor was poured off, and
immediately ferved up in cups.

From the refults of feveral experiments, which I
made with great care, in order to afcertain what

* V

proportion of the aromatic and volatile particles in
the Cpffee efcape, and are left in this procefs, l

found

essay xviii.] and the Art of preparing it. 175

found reafon to conclude, that it amounts to con-
fiderably more than half. This lofs may eafily be
explained ; it is occafioned principally, no doubt,
by the motions into which the liquid is thrown in
being heated, and afterwards on being made to boil ;
but there are two other unfavourable circumftances
attending this procefs that deferve attention.

The air that is attached to the fmall folid particles
of the ground Coffee, often remain attached to
them, and caufmg them to rife up to the furface of
the water, and to remain there, thefe particles con¬
tribute very little to the ftrength or qualities of the
liquor \ and even thofe particles which, becoming
thoroughly foaked with the water, are mixed with
it ; as they are furrounded, not by pure water, but
by a folution of Coffee, more or lefs faturated, that
circumftance is unfavourable to their folution.

It is well known to chemifts, that any folid fub-
ftance, which is foluble in any liquid menftruum, is
diffolved with greater difficulty, or more flowly,
as the liquid is more charged with that fubftance.

Now, when Coffee is made in the mod advan¬
tageous manner, the ground Coffee is preffed down
in a cylindrical veffel, which has its bottom pierced
with many fmall holes, fo as to form a ftrainer,
and a proper quantity of boiling hot water being
poured cautioufly on this layer of Coffee in powder,
the water penetrates it by degrees, and after a cer¬
tain time begins to filter through it.

o 4 This

I

176 Of Coffee , [essay xviii.

This gradual percolation brings continually a fuc-
cellion of frefh particles of pure water into contaQ:
with the ground Coffee, and when the lafl portion
of the water has paffed through it, every thing
capable of being diffolved by the water, will be
found to be fo completely wafhed out of it, that
what remains will be of no kind of value.

It is however neceffary to the complete fuccefs of
this operation, that the Coffee fhould be ground
to a powder fufliciently fine, as has already been
obferved.

This method of making Coffee, by percolation,
has been pra&ifed many years, and its ufefulnefs is
now univerfally acknowledged. I do not know
who was the firfl to propofe it, but being thoroughly

perfuaded of the merit of the contrivance, I have

>

been defirous of recommending it ; and I conceived
that the moil effectual way of recommending it,
would be to explain the mechanical and chemical
principles on which its fuperiority depends.

In order that the Coffee may be perfectly good*
the flratum of ground Coffee, on which the boiling
water is poured, mull be of a certain thicknefs*
and it muff be preffed together with a certain de¬
gree of force. If it be too thin, or not fufficiently
preffed together, the water will pafs through it too
rapidly ; and if the layer of ground Coffee be too
thick, or if it be too much preffed together, the
water will be too long in paffmg through it, and
the tafte pf the Coffee will be injured.

Another

essay xviii.] and the Art of preparing it , 177

Another circumdance, to which little attention
has hitherto been paid, but which I have found to
be of confiderable importance, is the levelling of
the furface of the ground Coffee, after it has been
put into the flrainer, before any attempt is made to
prefs it together.

*

When the ground Coffee is poured into the
drainer it always (lands much higher in one part of
this veffel than elfewhere ; and if, in that fituation,
it be preffed down on the perforated bottom of this
veffel, without being previoufly levelled, it will be
much more preffed in fome parts than in others 5
and as the water will not fail to pafs mod rapidly,
where it meets with the lead refidance, a confider¬
able portion of the ground Coffee wall be fo crouded
together as to prevent the water from paffmg through
it, and confequently will contribute little or nothing
to the drength of the beverage.

To remedy this inconvenience, I ufe the follow¬
ing fimple contrivance : The circular plate of tin,
with a rod fadened to its centre, which ferves as a
rammer for preffing down the ground Coffee, has
four fmall projecting fquare bars, of about one-
tenth of an inch in width, fadened to the under
fide of it, and extending from the circumference of
the plate to within about one quarter of an inch
of its centre.

On turning this plate round its axis, by means
of the rod which ferves as a handle to it, (the rod
being made to occupy the axis of the cylindrical

veffel,)

a 78

Of Coffee, [essay xviii*

veffel,) the proje&ing bars are made to level the
ground Coffee ; and after this has been done, and
not before, the Coffee is preffed together.

This circular plate is pierced by a great number
of fmall holes, which permit the water to pafs
through it, and it remains in the cylindrical veffel
during the whole of the time that the Coffee is
making. It repofes on the furface of the ground
Coffee, and prevents its being thrown out of its
place by the water which is poured on it.

The rod which ferves as a handle to this circular

- • . 1

plate is fo fhort, that it does not prevent the cover
of the cylindrical veffel from being pirt down into
its place.

After having made a great number of experi¬
ments, in order to determine what thicknefs is belt
for the layer of ground Coffee, I have found that
two-thirds of an inch anfwers bell for the Coffee in
powder, before it is preffed together, and that it
ought to be fo preffed as to be reduced to the thick¬
nefs of fomething lefs than half an inch.

And as the quantity of ground Coffee neceffary
for making a cup of good Coffee (a quarter of an
ounce averdupois) juft fills a cylindrical meafure,
which is 1. 1 5 inches in diameter and in height,
its volume amounts to 1.1945 cubic inches; con-
fequently, a cylindrical veffel (which I fliall call
the drainer) proper for making one cup of Coffee ,
piuft be of fuch diameter that 1.1945 cubic inches

of

essay xviii.] and the Art of preparing it. 179

of ground Coffee will fill it to the height of two-
thirds of an inch.

On making the computation, it will be found
that one inch and a half is the moft proper diameter
for the fhainer to be employed in making one Tin¬
gle cup of good Coffee. And as the thicknefs of

i

the flratum of ground Coffee mufl always be the
fame, whatever may be the number of cups that
are made at the fame time ; the diameter of flrainers.

different fizes, will be

as

follows, viz.

Inches.

For 1 cup -

*

-

a»

i-5

2 - -

-

-

2. 1213

3 - -

«

V

-

2.5986

4 • *

-

-

3

5 - -

m

*

-

3-3541

6 - -

to

-

3.6742

7 - -

to

*

-

3.9687

8 - -

T, / •*

-

-

4.2426

9 - •

to

.

-

4-5

JO - -

to

-

47434

f

il - -

to

-

4-9749

and for 1 2 - -

„ * > a

to

to

5-«9 62

For common ufe, the following fizes will anfwer
very well ; and, in order that workmen may not
have the trouble of computing the heights of the
cylindrical veffels, which I have called ftrainers,
which contain the water that is poured on the

ground

i. So- Of Coffee, [essay xvni.

ground Coffee, I have given thefe heights in the
following Table. They have been determined on
the fuppofition, that the diameter of the veffel is
always juft equal to the diameter of the perforated
bottom by which it is clofed below ; and that the
quantity of water neceffary for making one cup of
Coffee, is 84 cubic inches.

A Table , fhewing the diameters and heights of
the cylindrical veffels (or ftrainers) . to be ufed in
making the following quantities of Coffee :

•uantity of Coffee to

Diameter of the

Height of the

be made at once.

{trainer.

{trainer.

1 cup «• -

14 inches

5^ inches.

2 CUpS * -

- 24 - -

- si

3 or 4 cups -

1

•

1

■ i

5 or 6 cups

- - 3i ' -

■ si

7 or 8 cups

• 4 -

- -si

9 or 10 cups

4t

- si

ii or 1 2 cups

‘ 5 -

- si

As there is fo little difference in the heights of
thefe ftrainers, and as a fmall additional height will
be rather advantageous than otherwife, I would
recommend them to be made all of the fame height,
viz. 57 inches in height.

As thefe ftrainers muft be fufpended in their re-
fervoirs, which are deftined for receiving the Coffee,
and at fuch a height that after ail the Coffee has

palled

I

essay xviii. j and the Art of preparing it . 18 i

paffed through the (trainer, the bottom of the
(trainer may (till be above the furface of the Coffee
in the refervoir ; it will be belt to make the refer-
voir of a Conical form, and juft large enough above
to receive the (trainer in fuch a manner that it may
be fufpended in the refervoir by means of a narrow
proj effing brim.

* The boiler in which the refervoir is fufpended
may likewife be made conical, and of fuch diameter
above, as to receive the refervoir in fuch a manner
as to be firmly united to it.

The refervoir and its boiler muft be foldered
together above, at their brims ; and the refervoir
muft be fufpended in its boiler in fuch a manner,
that its bottom may be about a quarter of an inch
above the bottom of the boiler.

The lmall quantity of water which it will be
neceffary to put into the boiler, in order that the
refervoir for the Coffee may be furrounded by
fleam, may be introduced by means of a fmall open¬
ing on one fide of the boiler, fituated above, and
near the upper part of its handle.

The fpout through which the Coffee is poured
out paffes through the fide of the boiler, and is
fixed to it by foldering. The cover of the boiler
ferves at the fame time as a cover for the refervoir,
and for the cylindrical drainer, and it is made
double, in order more effectually to confine the
heat.

The

i Si 6/ Coffee , [essay xvnn

The boiler is fixed below to a hoop, made of
fheet-brafs, which is pierced with many holes* This
hoop, which is one inch in width, and which is
firmly fixed to the boiler, ferves as a foot to it,
when it is fet down on a table, and it fupports it
in fuch a manner, that the bottom of the boiler is
elevated to the height of half an inch above the
table.

When the boiler is heated over a fpirit lamp, or
over a fmall portable furnace in which charcoal is
burnt, as the vapour from the fire will pafs off
through the holes made in the Tides of the hoop,
the bottom of the hoop will always remain quite
clean, and the table-cloth will not be in danger of
being foiled, when this coffee-pot is fet down on
the table.

A /

As the hoop is in contact with the boiler, in
which there will always be Tome water, it will be
fo cooled by this water as never to become hot
enough to burn the table-cloth.

The bottom of the boiler may be cleaned occa-
fionally, on the underfide with a brufh or a towel,
but it fhould not be made bright, for when it is
bright it will be more difficult to heat the water in
it than when it is tarniflied and of a dark brown
colour.

But the Tides of the boiler fhould be kept as
bright as poffible, for when its external furface is
kept clean and bright, the boiler will be lefs cooled
by the furrounding cold bodies, than when its

metallic

essay xviii.] and the Art of preparing if: 1 83

metallic fplendour is impaired by neglecting to
clean it *.

As the fmall quantity of water which is put into
the boiler ferves merely for generating the fleam
which is neceffary in order to keep the refervoir and
its contents conflantly boiling-hot ; if the refervoir
be made of filver, or even of common tin, the boiler
may, without the fmallefl danger, be made of

■>%

* I have in my pofiefiion two porcelaine tea-pots of the
fame form and dimenfions, one of which is gilt all over on the
outfide, and might eafily be miitaken for a gold tea-pot ; the
other is of its natural white colour, both within and without ;
being neither painted nor gilt. When they are both filled
at the fame time with boiling water, and expofed to cool in
the fame room, that which is gilt retains its heat half as long
again as that which is not gilt. The times employed in cool¬
ing them, a given number of degrees, are as three to two.

The refult of this interefting experiment (which I firfl made
about feven years ago) afFords a good and fubftantial reafon for
the preference which Englifh ladies have always given to
filver tea-pots. — The details of this experiment may be Ten
in a paper publifhed in the Memoirs of the French National
Inflitute for the year 1807.

I have likewife a fet of tea-cups, and another of coffee-cups,
which are gilt on the outfide, and they preferve the heat of
thofe liquids, much longer than China-cups which are not
fo gilt.

Little advantage would be derived from gilding them on the
infide, and none at all if they were filled quite full with the hot
liquid.

I have found that all metals are alike ufeful in preferving
heat (or cold), provided their furfaces be quite clean and

copper ;

184 Of Coffee , [essay xvnn

copper ; or of copper plated with filver, which will
give to the boiler an elegant appearance, and at the
fame time render it eafy to keep it clean on the
outftde.

The boiler may likewife be made of tin, and
neatly japanned on the outftde, provided the hoop
to which it is fixed below be made of copper, but
this hoop muff never be japanned nor painted ;
and it mu ft always be made of fheet-copper or
filver ; and the boiler muft always be heated over a
fmall portable fire-place or lamp, fomewhat lefs in
diameter above, than the hoop on which the boiler
is placed.

In order that the flat bottom of the boiler may
not Another and put out the fire, the brim of the
fmall furnace or chafftng-difh, which is ufed, muft
have fix projecting knobs, at the upper part of it,
each about one quarter of an inch in height, on
which the bottom of the boiler may reft.

If thefe knobs (which may be the large heads of
fix nails), be placed at equal diftances from each
other, the boiler will be well fupported ; and as
the hot vapour from the fire will pafs off freely
between them, the fire will burn well. As a very
fmall fire is all that can be wanted, no inconve¬
nience whatever v/ill arife from the heating of the
boiler on the table, in a dining-room or breakfaft-
room, efpecially if a fpirit lamp be ufed, and the
quantity of heat wanted is fo very fmall, when the

water

essay xviii.] and the Art of preparing it, 185

water is put boiling hot into the boiler, that the
expence for fpirits of wine, would not, in London,
amount to one penny a day, when Coffee is made
twice a day for four perfons.

It is a curious fa£l, but it is nevertheless moft
certain, that in fome cafes , fpirits of wine is cheaper,
when employed as fuel, even than wood. With
a fpirit lamp, conftru&ed on Argand’s principle,
but with a chimney made of thin flieet iron, which
I caufed to be made about feven years ago (and
which has fince become very common in Paris #),
I heated a fufficient quantity of cold water, to make
Coffee for the breakfaft of two perfons, and kept
the Coffee boiling hot, one hour after it was made ;
with as much fpirits of wine as coft two fous , or one
penny Englifh money.

A fire could not have been made with wood at a
lefs expence to heat this water.

As the fize of the flame of this lamp may be in-
creafed or diminifhed, at pleafure, by means of the
rack which raifes and lowers its circular wick, all
the fuel which is confumed is ufefully employed,
and no heat is wafted in forming fleam, when
nothing more is wanted than the prefervation of the
temperature at which water is difpofed to boil.

* I intend, if poffible, to fend one of thefe fpirit lamps to
England, with this Effay, in order that it may be put into the
hands of fome workman there, who may be difpofed to imi¬
tate it.

VOL. IV.

P

In

1 86 Of Coffee, [essay xviii.

In order to convey diftind ideas of the different
parts of the apparatus neceffary in making Coffee
in the manner I have recommended, I have added
the figure i, which reprefents a vertical fedion
(drawn to half the full fize) of a coffee-pot con-
ftruded on what I conceive to be the very belt
principles. Its fize is fuch as is moll proper for
making four cups of Coffee at once.

a— is the cylindrical ftrainer, into which the
ground Coffee is put, in order that boiling hot
water may be poured on it ; when this ftrainer
is filled with boiling water (after an ounce of
ground Coffee has been properly preffed down
on its bottom) the quantity of the liquid is juft
fufficient for making four cups of Coffee.
b — is the ground Coffee in its place.
c — is the handle of the rammer which is repre-
fented in its place.

d — is the refervoir for receiving the Coffee which
defcends into it from the ftrainer ; and
e — is the fpout through which the Coffee is
poured out.

/-is the boiler, into which a fmall quantity of
water is put, for the foie purpofe of generating
fleam, for keeping the refervoir hot.
g — is the opening by which the water is poured
into the boiler or out of it ; this opening has a
flat cover, which moves on a hinge, that is re-
prefented in the figure. The

essay xvhi. 2 and the Art of preparing it. 187

The boiler is of a conical form, and is enlarged
a little at its upper extremity, in order to re¬
ceive the cover which clofes it above.

The refervoir and the boiler are fixed together
above by foldering, fo that the refervoir remains
fufpended in the boiler.

The cylindrical drainer is fufpended on the upper
extremity of the refervoir, by means of a flat
projecting brim, about two-tenths of an inch
broad.

h — is the hoop, made of fheet-copper, and per-
forated with a row of holes, on which the
boiler repofes : a part of the bottom of the
boiler is feen through thefe holes.

The refervoir is reprefented by dotted lines, in
order the better to diftinguifh it.

The opening in the fide of the boiler, by which
the water enters it, is reprefented in the figure.
This opening is covered by a part of the handle of
the coffee-pot.

The diameter of the hoop h , on which the
coffee-pot flands, fhould always be at lead fix inches
in diameter whatever may be the contents of the
coffee-pot ; and the fpirit lamps or portable fur¬
naces, ufed with thefe coffee-pots, fhould always be
rather lefs than fix inches in diameter above , or at
their openings, in order that the bottom of the
coffee-pot may, in all cafes, be fet down properly
on the fix knobs belonging to the lamp or the fur¬
nace, which are deftined to fupport it.

p 2

The

f

1 88 Of Coffee , [essay xviii.

The figure 2. has been added, in order to fhew
how the fame coffee-pot may be made to ferve for
making any number of cups of Coffee, within cer¬
tain limits, that may be wanted, by being furnifhed
with flrainers of different fizes.

This coffee-pot has three flrainers, the largefl of
which is cylindrical, and of a fize proper for mak¬
ing either Jive or fix cups of Coffee.

The fecond in fize, is defigned for making
either three cups or four cups. It is compofed of
two tubes or cylinders, of different diameters,
united together. The lower cylinder, which is one
inch in length, and two inches and three quarters
in diameter, is clofed below by a perforated
bottom, on which the ground Coffee is placed.
The upper cylinder, which is united to it, is about
three inches in length, and juft wide enough to
enter without difficulty, into the larger cylindrical
firainer, on the top of which it repofes by means of
a projecting brim, when not in ufe.

The fmaller drainer, which is of a fize proper
for making two cups of Coffee, enters that lad de¬
fer ibed, and repofes on it (when not in ufe). This
drainer is alfo compofed of two cylinders united
together. That which is lowed is two inches and
one eighth in diameter and one inch in height,
clofed below by a flat bottom, perforated with fmall
holes. The other cylinder, which is united to it
above, is of fuch a diameter as to enter the fecond
drainer without difficulty, and of the height which

is

essay xviii.] and the Art of preparing it. 189

is neceffary, in order that it may contain two coffee-
cups full of water.

Each of thefe ftrainers has its feparate rammer to
ram down the ground Coffee placed in it, but one
common handle ferves for them all. This handle is
fcrewed into the middle of a circular plate, which
forms the principal part of the rammer.

The circular plate which belongs to each of thefe
ftrainers, remains in it, when the coffee-pot is not
in ufe, and the handle remains attached to the cir¬
cular plate belonging to the fmaller ftrainer.

When only two cups of Coffee are wanted, the
two largeft ftrainers being taken away, the fmaller
ftrainer is ufed alone.

If either three or four cups are wanted, the fmalleft
and the largeft ftrainers are taken away, and the
other ftrainer is ufed.

When five or fix cups are wanted, the largeft
ftrainer is ufed, and the other two are taken
away.

If feven , eight, nine , or ten cups are wanted, fix
cups are firft made with the largeft ftrainer ; when
that ftrainer being removed, the remaining number
of cups are made with the ftrainer next in fize.

By making ufe of the three ftrainers one after
the other, eleven or twelve cups of Coffee may be
made in this coffee-pot, and as the heat always re¬
mains the fame during the whole of the time em¬
ployed in thefe operations, the Coffee is juft as good
as if the whole of it were made at once.

p 3

By

i go Of Coffee , [essay xviii.

By adding two additional ftrainers to the coffee*
pot reprefented by the figure 1. one of them of a
proper fize for making one cup of Coffee ; and the
other of a proper fize for making two cups ; this
coffee-pot may be ufed for making either one , two,
three , four , or fix cups of Coffee.

All the coffee-pots that have been made of this
fize, have been furnifhed with thefe two additional
ftrainers ; but they were omitted in the figure, in
order to render it more fimple, and more eafy to be
underftood.

Moft of the coffee-pots of this fize (figure i.)
have had their boilers made fufficiently capacious
for heating the water neceffary for making the
Coffee, as well as that which is required for gene¬
rating the fleam which is employed for keeping the
refervoir boiling hot.

This may be done in all cafes ; but when this
method is employed, it will be neceffary that the
boiler fhould be furnifhed with a brafs cock, placed
about one quarter of an inch above the level of its
bottom, in order that the boiling water neceffary
for pouring on the ground Coffee in the ftrainer
may be drawn off, without removing the boiler
from the fire. By placing this brafs cock imme¬
diately under the handle of the coffee-pot, it may
be fo united to it as almoft to efcape obfervation.
I have a coffee-pot of this kind, in which the brafs
cock, by which the boiling water is drawn off, is
entirely concealed in the ornaments of the handle.

I have

essay xviii.] and the Art of preparing it. 191

I have another, in which the boiling water is
poured out by means of a fecond fpout, placed juft
oppofite to that by which the Coffee is poured out ;
but in ufing this coffee-pot, it is indifpenfably ne-
ceffary to pour out at once all the boiling water
that is wanted, and before any water has been put
into the ftrainer.

When coffee-pots are made with two fpouts, one
for the water, and the other for the Coffee, the
handle mult be placed between them, and at equal
diftances from each of them.

I have caufed a very beautiful urn to be con-
ftru&ed, with a concealed fpirit lamp, which ferves
for heating water for making either tea or Coffee, and
for making both tea and Coffee at the fame time. It
is reprefented by the figure 3, which is drawn to a
fcale of one quarter of the full fize.

This urn is placed on what appears to be a block
of black marble, feven inches fquare, and two
inches and a quarter in thicknefs. This is made of
ftrong fheet iron, japanned black, which ferves for
concealing a fpirit lamp, on Argand’s principles,
which is employed in keeping the water in the urn
boiling hot. The foot of the urn is hollow, and
ferves for concealing the chimney of the lamp.

It is perforated by two rows of fmall round holes,
the one in the moulding at its lower extremity ;
which ferves for the admiftion of the air, which is
neceffary for keeping the lamp burning ; the other
near the upper extremity of the foot where it is

p 4 united

i $2 Of Coffee $ [essay xvm.

united to the body of the urn, which ferves as a
paflage for the efcape of the vapour, which is gene¬
rated in the combuftion of the ardent fpirits.

There is a large circular hole in the top of the
fquare box (of Iheet-iron), on which the urn is
placed, which hole is covered and completely con¬
cealed by the foot of the urn.

This hole, which is five inches and a half in
diameter, is the paflage by which the lamp enters
when it is placed in the fquare box : and by means
of a rim about a quarter of an inch in width and
five inches and a half in diameter, which is fixed
to the lower part of the foot of the urn, and which
enters the circular hole in the top of the box ; by
turning round the urn to the left, one quarter of a
whole revolution, the rim attached to the foot of
the urn being in its place, the urn and the fquare
box are locked together, in a manner fimilar to
that which is ufed in fixing a bayonet to its
mulket ; and in taking up the urn by its two
handles, the fquare box is taken up along with it,
and remains firmly attached to it.

The fize of the flame of the lamp is regulated,
and the lamp is extinguiflied when no longer
wanted, by means of a rack which moves the
wick of the lamp up or down ; and this rack is
moved by means of a horizontal rod of ftrong
wire, which lies in a fmall groove made to receive it
in the top of the fquare box. This wire has a fmall
knob at the end of it, which projects juft beyond

the

essay xvm.] and the Art of preparing it. 193

the fide of the box ; and as both this wire and the
knob at the end of it are painted black and
japanned, they are little obferved, and confequently
do not produce any difagreeable effed.

Two brafs cocks (which are not reprefented in
the figure) are placed at the diftance of about four
inches from each other, at the level of the bottom
of the refervoir which ferves for containing the
Coffee, when made ; one of thefe ferves for drawing
off the boiling water contained in the boiler, and
the other for drawing off the Coffee ; and the words
Water and Coffee are infcribed on their handles.

This urn has one large cover, nine inches in
diameter, which clofes the boiler without doling the
opening of the refervoir for the Coffee, and which
appears to form the upper part of the urn ; and
another cover, about four inches and a quarter in
diameter, which being made to fit into a circular
hole in the top of the cover of the boiler, clofes
the refervoir, which contains the cylindrical ftrainer
and the Coffee.

When the boiler is filled with boiling water both -
covers muft be removed ; but the fmall cover only
is removed when the ground Coffee is put into the
ftrainer ; and when boiling water (which may be
drawn out of the boiler) is poured on it.

The refervoir for the Coffee is firmly fixed in its
place, in the middle of the boiler, by means of
three fhort feet of ftrong tin (of about half an inch in

height).

194 Of Coffee , [essay xviii,

height), which are foldered to the refervoir, and to
the boiler.

The form of the refervoir is conical, and it is
about fix inches in diameter below, four inches and
one*tenth in diameter above, and feven inches and
a half in height.

By ufing two or three (trainers fucceffively, fix -
teen or eighteen cups of Coffee may be made in this
urn ; and when the flrainers are taken away, and
the refervoir is quite filled with Coffee, it will hold
more than twenty cups.

This urn has been found to be very ufeful for
ferving up Coffee after dinner to large companies ;
and it is the more fo, as thofe who find their Coffee
too ftrong can eafily make it weaker, by mixing
with it a little boiling water, which may be drawn
from the boiler, which is always at hand.

The form of the boiler, and that of its large
cylindrical ftrainer, are faintly reprefented in the
figure by dotted lines.

The boiler muff always be filled with water already
boiling hot ; for the lamp, though quite powerful
enough to keep this water boiling hot, and even to
make it boil with violence, does not furnifh heat
enough to heat fo great a quantity of cold water,
and make it boiling hot in any reafonable time.

As often as the fmalleft quantity of fleam is feen
to iffue from the boiler, the flame of the lamp
fhould be reduced, for no advantage whatever at¬
tends

essay xviii.] and the Art of preparing it. 195

tends the actual boiling of water, which is boiling
hot ; and it always occafions a very great lofs of
heat, and fills the room full of fleam and of in-
vifible vapour, which makes every thing in it damp
and uncomfortable.

A confiderable number of thefe Coffee urns
have been made and fold at Paris within thefe lafl
five or fix years ; fome of them have been made
of filver richly fculptured and ornamented by
gilding. Several others have been made of copper
and ornamented with copper plated with filver ; thefe
lafl, with their lamps, and a fet of three flrainers
made of tin, have cofl about fix guineas. But the
greater part of thofe which have been fold, have
been made of tin ; and they have in general been
gilt fo as to be entirely covered over on the outfide
with leaf gold, and this leaf gold covered by a
coating of tranfparent varnifh.

When fo conflru&ed and ornamented, they have
cofl four guineas with all their apparatus quite
complete.

I cannot help flattering myfeif that they will find
their way into England, and there meet with ap¬
probation. I fhall never ceafe to be particularly
defirous that my labours to improve the domeftic
arts may be found ufeful in that country.

The figure 4. reprefents a fmall urn with two
fliort fpouts and two handles, of a proper fize for
making one fmgle cup of Coffee. It is drawn to
a fcale of half the full fize. Its boiler contains

10

water

196 Of Coffee , [essay xviii.

water enough to furniffi what is required for making
the Coffee, as well as that which is neceiTary for
generating fleam, for keeping the Coffee hot. The
water defcends below the foot of the urn into the
flat plinth, on which it flands, and to which it is
united.

The figure 5. reprefents an urn with two long
fpouts, which ferve at the fame time as handles.
Its fize is fuch as would be proper for making either
one or two cups of Coffee. The (trainer, which is
reprefented by dotted lines, is of a proper fize for
making two cups.

Both thefe urns are deflined to be heated over
fpirit lamps, or fmall portable furnaces.

It is hardly neceffary that I fhould obferve, that
in cafe the forms of either of thefe urns fhould
be thought inelegant, their fizes may, without any
difficulty, be confiderably augmented ; but when
fpouts are ufed with large urns, they occafion a
good deal of inconvenience.

As Coffee is very wholefome, and may be afforded
at a very low price, efpecially in countries which
have colonies where the climate is proper for grow¬
ing it, many public advantages would be derived
from the general introdudion of it among all claffes
of fociety.

One mod important advantage, which, on a fu-
perficial view of the fubjed, is not very obvious,
would mod probably be derived from it. As Coffee
poffeffes, in a high degree, an exhilarating quality,

it

essay xviii.] and the Art of preparing it, 197

it would, in fome meafure, fupply the place of
fpirituous liquors among the lower claffes of the
people.

Thofe who work hard, Hand in need of fome-
thing to cheer and comfort them, from time to
time, and it is greatly to be lamented that the
flrong liquors now ufed for that purpofe, are not
only very unwholefome and permanently debilitating,
both to the mind and the body, but that their
operation is accompanied by a peculiar fpecies of
madnefs, which renders thofe who are under the
influence of it very mifchievous, and fo loll to all
fenfe of decency and propriety, as to become objects
of horror and averfion.

The pleafing flow of fpirits that is excited by
Coffee, has none of thefe baneful effects.

Inflead of irritating the mind, and exciting to
acts of violence, it calms every turbulent and ma¬
levolent paffion, and is accompanied by a confciouf-
nefs of eafe, contentment, and good-will to all
men, which is very different from that wild joy
and unbridled licentioufnefs which accompanies in¬
toxication.

Coffee is not only very wholefome, but when
fweetened with fugar, is very nourifhing.

Sugar is fuppofed to be the moil nourifhing fub-
fiance known. ~ Its nourifhing powers are even
fuch, that the ufe of it has been recommended in
fattening cattle.

An

[essay XVIII.

198 Of Coffee ,

An ingenious young man, Doftor - — — , a

phyfician, who refided in London, made a long
eourfe of experiments on himfelf, feveral years ago,
with a view to determine the relative nutritive powers
of thofe fubftances which are moil commonly ufed
as food by mankind, and he found that fugar
was more nourilhing than any other fubftance he
tried.

He took no other food for a confiderable time,
than fugar, and drank nothing but water ; and he
contrived to fubfift on a furprifingly fmall quantity
of fugar. If my memory does not fail me, it was
no more than two ounces a day.

It is much to be lamented, that this iitferefting
young man Ihould have fallen a facrifice to his zeal
in promoting ufeful fcience ; but his health was fo
totally deranged by thefe experiments, which he
purfued with too much ardour and perfeverance,
that he died foon after they were finilhed. All the
refources of the medical art were employed, but
nothing could fave him.

As common brown fugar is quite as nourilhing as
the belt refined loaf fugar, and as a great many
perfons prefer it for Coffee, it appears to me to be
extremely probable that Coffee may be found to be
one of the cheapefl kinds of food that can be pro¬
cured, and more efpecially in Great Britain.

Half a pint of the bell Coffee, or two full cups,
may be made with half an ounce of ground Coffee,
which, if one pound averdupois weight of raw

Coffee

essay xviii.] and the Art of preparing it. 199

Coffee can be bought in the {hops for twelve-pence
fterling, will coft only fix-fevenths of a farthing;
and if a pound of brown fugar can be bought for
one {hilling, one ounce of fugar, which would be
a large allowance for two cups of Coffee, would
coft only three farthings ; confequently the materials
for making half a pint of Coffee would coft lefs
than one penny.

As Coffee has a great deal of tafte, which it im¬
parts very liberally to the bread which is eaten with
it, and as the tafte of Coffee is very agreeable to all
palates, and the ufe of bread greatly prolongs the
duration of the pleafure which this tafte excites, a
very delicious repaft may be made merely with
Coffee and bread, without either butter or milk.

The tafte of the Coffee predominates in fuch a
manner, that the butter would hardly be perceived,
and might be omitted without any fenfible lofs. But
I acknowledge, that in my opinion, the addition of
a certain quantity of good cream or milk to Coffee,
improves it very much. Milk, however, is not
a very expenfive article in Great Britain ; and if
the butter be omitted, which is by no means necef-
fary, (and is even unwholefome,) a good breakfaft
of milk Coffee might be provided for a very fmall
fum.

What a difference between fuch a breakfaft, and
that miferable and unwholefome wafh which the
poor people in England drink under the name of
tea!

All

200 Of Coffee , [essay xviil

All the Coffee that can be wanted, may be had
In the Britifb colonies, and paid for in Britifh manu¬
factures ; but tea muff be purchafed in China, and
paid for in hard money.

Thefe are circumftances which ought, no doubt,
to have great weight, efpecially in fuch a country as
England, where all ranks of fociety are equally
fenfible of the advantages of their diftinguifhed
fituation, and equally anxious to promote the public
profperity.

There are fome difficulties, no doubt, in chang¬
ing the habits of a nation, but thefe difficulties have
been too much exaggerated, and they have too
often been an excufe for indolence.

If any thing really ufeful be propofed to the
public, it can hardly fail to be adopted, if it be
properly recommended ; but fo many new things,
unworthy of notice, are every day propofed, that
it is by no means furprifing that little attention is
paid to fuch recommendations.

Many ufeful improvements have been propofed
by ingenious and enlightened men, which have
failed, merely becaufe thofe who have brought them
forward have negleCted to give directions fufficiently
clear refpeCting the details of their execution.

I have been fo much perfuaded of that important
faCt, that I have perhaps fometimes erred on the
other fide, and taken up too much time in deferr¬
ing things, in all their moll minute details, which
many perfons would be able to comprehend at

once.

201

essay xviii.] and the Art of preparing it.

once, and almod without any defcription ; but I
have done that which I thought moil likely to ren¬
der my labours ufeful.

I never write, except it be to recommend to the
public fomething which I conceive to be of import¬
ance, or to communicate the refuits of new experi¬
mental refearcbes, which appear to be fufficiently
curious and intereding to merit attention ; and it
muft, I think, be quite evident to thofe who read
my writings, that I have never hefitated to facrifice
to perfpicuity, not only every ornament of dyle,
but alfo every brilliant idea which, by getting too
ftrong hold of the imagination, might dillraft the
attention.

The reader mull condefcend not only to go with
me frequently into the humbled; walks of private
life, but alfo to examine the various objects that
prefent themfelves, with the greated care, and in all
their molt minute details.

But I mud haden to put an end to this Effay,
which has already exceeded the limits to which I
had hopes of being able to confine it. Being
anxious that it might be read by many perfons, (as
I thought that it would be very ufeful,) I felt the
neceflity of making it as fhort as poflible. I fhall
conclude with a few obfervations on the means that
may be employed for rendering the ufe of Coffee
more general among the lower claffes of fociety.

In the fird place, the method of making good
Coffee mud be known ; and the utenfils necelfary in
vol. iv. q that

»

202 Of Coffee , [essay xviir*

that procefs mull be fo contrived, as to be cheap
and durable, and eafy to be managed.

It will be in vain that the laws are repealed which
laid reftriffions on the free ufe of Coffee, as long
as the great mafs of the people remain ignorant of
its excellent qualities ; they will be little difpofed to
fubftitute it in the place of another beverage, to
which long habit has given them an attachment.

As long as Coffee lhall continue to be made
according to the method generally practifed in
England, I lhall have no hope of its being preferred
to tea, for its qualities are fo inferior when prepared
in that way, that it is hardly poffible that it Ihould be
much liked.

The utenfiis which I have recommended for
making Coffee, though feme of them are fufficiently
limple to be afforded at a low price ; yet, as they
are contrived to be ufed with fpirit lamps, or with
portable furnaces, which mull be heated with
charcoal, they are not well calculated for the ufe
of thofe perfons who inhabit the rooms in which
they cook their viduals ; and of many others, who
though they may have feparate kitchens, may not
find it convenient to ufe fpirit lamps and portable
furnaces.

For the ufe of fuch perfons, the coffee-pots repre-
fented by the figures i. and 2. may be made to
anfwer perfectly well, merely by taking away the
perforated hoops on which they Hand. For, when
thefe are taken away, thefe coffee-pots may be heated

over

essay xviir.] and the Art of preparing it . 203

over a common chimney fire juft as any common
coffee-pot is now heated.

For very poor perfons, who cannot afford to
buy a coffee-pot, I {hall recommend a very fimple
contrivance, by means of which Coffee may be
made, and even in the L: heft poftible perfection.
— I have often made ufe of this contrivance in
making my own breakfaft, and I have not found
the Coffee to be in the leaft inferior to that made
in the moft coftly and complicated machines.

This little utenfil is diftinCFy reprefented in the
figure 6. which is drawn to a fcale of half the
full fize.

The whole of this apparatus confifts of a coffee-
cup, which {hould hold about three quarters of a
pint ; and a ftrainer, made of tin, which is fufpended
in it by its brim.

This coffee-cup fhould be cylindrical, and when
employed in making one gill of good ftrong Coffee,
{hould be three inches in diameter within, and three
inches and a half deep. The lower part of the
ftrainer is one inch and a half in diameter, and one
inch deep ; and the upper part of it two inches and
nine-tenths in diameter, and about one inch and a
half in depth.

* *

The wrater which is poured on the ground Coffee
{hould be boiling hot ; the cup and the ftrainer
having both been previoufly heated, by dipping
them into boiling water.

q 2

As

204 Of Coffee , [ESSAY xvm.

As the Coffee will not be more than eight or ten
minutes in palling through the flrainer, it is pro¬
bable that it will be quite as hot as it can be drank,
after it has defcended into the lower part of the
cup ; but if it fhould be necelfary to keep it hot a
longer time, the cup may be placed in a fmall quan¬
tity of boiling water, contained in a fmall faucepan,
or other fit veffel, placed near the fire.

When all the Coffee has palled into the lower
part of the cup the drainer may be taken away, and
the cup may be coyered with the cover of the
drainer.

I do not think it poffible to contrive a more fimple
apparatus than this for making Coffee, nor one in
which Coffee can be made in higher perfe&ion.

That reprefented by figure 7., which is of a fize
proper for making two cups of coffee, is equally fim¬
ple ; and as it may be made entirely of pottery, it
would coll a mere trifle, perhaps not more than a
fhilling.

The cup, which ferves in two capacities, firfl as a
refervoir in making the coffee, and then as a cup in
drinking it, (and which, in a family, may be ufed
for other purpofes,) is three inches and a half in
diameter, internally, and four inches deep.

As many perfons may prefer coffee-pots made
entirely of Staffordfhire-ware, porcelain, or other
pottery, to thofe made of the metals, not only on
account of the low prices at which they may be
1 o afforded.

essay xviii.] and the Art of preparing it . 205

afforded, but alfo on account of their fuperior neat-
nefs and cleanlinefs, I have added the figure 8.,
which, on a fcale of half the full fize, reprefents a
coffee-pot made of pottery, of a fize proper for
making five or fix cups of coffee at once, or three,
four, five, fix, feven, or eight cups, if two {train¬
ers are ufed, one after the other.

When this coffee-pot is ufed, it will be neceffary
to place it in boiling water to keep it hot, and it will
be ufeful to cover the whole with a cylindrical veffel
turned upfide down ; by which means both the
ftrainer and the coffee-pot will be furrounded by hot
{team, which will contribute very effentially to the
goodnefs of the Coffee.

As foon as the Coffee has paffed into the coffee¬
pot the (trainer may be taken away ; and the coffee¬
pot covered with the cover, which is common to it,
and to the {trainer.

I {hall conclude by a few obfervations, on the
means that may be ufed for preferving ready made
Coffee, good for a confiderable time, in bottles.

The bottles having been made very clean, muff
be put into clean cold water, in a large kettle, and
the water muff be heated gradually, and made to
boil, in order that the bottles may be heated boil,
ing hot.

The Coffee, frelh prepared and {till boiling hot,
mult be put into thefe heated bottles, which muff
be immediately well clofed with good found corks.

The

2q6 Of Coffee , [essay xviii.

The bottles muft then be removed into a cool
cellar, where they muft be kept well covered up in
dry fand, in order to prefer ve them from the light*

By this means ready-made Coffee may be pre-
ferved good for a long time, but great care muft be
taken not to let it be expofed to the light, otherwife
it will foon be fpoiled.

When wanted for ufe the Coffee muft be heated
in the bottle and before the cork is drawn ; other-
wife a great deal of the aromatic flavour of the
Coffee will be loft in heating it. And in order that
it may be heated in the bottle, without danger, the
bottle muft be put into cold water, and this water
muft be gradually heated till the Coffee has ac¬
quired the degree of heat which is wanted. The
cork may then be drawn, and the Coffee poured
out, and ferved up.

As good Coffee is very far from being difagree-
able when taken cold, and as there is no doubt but
it muft be quite as exhilarating when cold as when
it is taken hot, why fhould it not be made to fupply
the place of thofe pernicious drams of fpirituous
liquors, which do fo much harm ?

Half a pint of good cold Coffee, properly fweet-
ened, which would not coft more than half a pint
of porter, would be a much more refrefhing and ex¬
hilarating draft ; and would no doubt be incompara¬
bly more nourifhing. \

How much then muft it be preferable to a dram
of gin!

The

I

essay xviii.J and the Art of preparing it . 207

The advantages and difadvantages to agriculture
and commerce, which would arife from the intro¬
duction of a new beverage for fupplying the place
of malt liquors and ardent fpirits diftilled from grain ;
muff be eilimated and balanced, by thofe whofe
knowledge of political economy fits them for deter¬
mining thefe moft intricate and important queftions.

END OF THE EIGHTEENTH ESSAY

Strahan and Preston,
Printera-Street, London.

Juji publifhed ,

BY T. CADELL AND W. DAVIES, STRAND,

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ALSO,

ESSAY XVI. Of the Management of Light in Illumi¬
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ESSAY XVII. An Enquiry concerning the Light which
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ThJjUshed Aug^i ,i&i2 .lyy T.CadeJlk W. Davie# Strand. L ondon .

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